Bifocal ophthalmic lens

ABSTRACT

An optical device comprising a body formed of two sets of alternately disposed light-transmitting laminar sections through which light from a common optical field is directed, the two sets of sections having different optical characteristics. In one form of the device, the first set of laminations comprises a lens of long focal length and the other set of laminations comprises a lens of long focal length whereby the optical device constitutes a bifocal lens. In another form of the optical device, the two sets of laminations constitute sections of prisms having different optical characteristics so that the images of objects in the field of view of the device are transmitted in different directions.

United States Patent 1191 Goldman et al.

May 7, 1974 1 ELECTRONIC TEXT DISPLAY AND PROCESSING SYSTEM Inventors: Arnold J. Goldman; Stephen L. Kurtin, both of Sherman Oaks; Carver A. Mead, Pasadena, all of Calif.

[73] Assignee: Lexitron Corporation, Chatsworth,

Calif.

[22] Filed: Jan. 18, 1973 [21] Appl. No.: 324,776

Primary Examiner-Paul J. Henon Assistant Examiner-Paul R. Woods [5 7] ABSTRACT An electronic test display and processing system having a display. a memory, and a manually operable data and control function entry device for interactive text processing by an operator via a keyboard whereby text entered on the display is modifiable under the control of the operator. By utilization of a position indicator or cursor which is positionable by the operator on the display screen at the desired position with respect to the text the operator can perform text editing functions such as adding'a character, deleting a character. adding or deleting a line of text, selecting a block of text from the display for deletion or insertion into another page of text displayed on the screen. or erasing text.

The text editing functions are accomplished by means of a processor receiving commands indicative of operator action as well as commands indicative of internal signals generated in proper time sequence to perform the functions selected by the operator. The memory includes a display memory capable of storing information in coded form for displaying'a full page of text; a character buffer for storing information indicative of two characters within a line of text, the two characters being the character currently being displayed as well as the character previously displayed; and a line buffer capable of storing two of the lines of textual information, one line being the line of text currently being displayed while the other line is the line of text previously displayed. Multiplexing and data selection means are provided for sequentially reconfiguring the flow of information through the various storage means within the memory to accomplish the text editing functions.

15 Claims, 88 Drawing Figures 1 2 18 32 34 36 4B 38 ,h, t X r' 2 1 TYPEWRITER s ug l g gpg DISPLAY KE A Qg INDICATOR EDIT/MERGE flg SELECT/INSERT l I I 0 A T A s u s 2 4 1O SPECIAL CONTROL AND l'NDlCATOR Bus go I 3 OPERATOR I] ADDRESS AND COMMAND BUS 2 Q I r M l N 3 5 u s Q I mafia; MEMORY hews? JUSTIF Y TAB PAGINATE PRINTER Ki van/ran l4 

1. A bifocal ophthalmic lens having a convex front surface and a concave rear surface, said lens comprising: a plurality of thin planar light-transmitting laminations extending transversely from the front to the back surface of the lens, said laminations being formed as a first and a second set and each lamination of the first set being bonded to a lamination of the second set in alternating sequence, one edge surface of each lamination of said first set being formed with a portion of a first common spherical curvature for distant vision, the corresponding edge of each lamination of said second set being formed with a portion of a second common spherical curvature different from said first curvature for near vision, whereby one of said front and rear lens surfaces defined by said edges provides the bifocal lens surface, the other of said surfaces having a continuous uniform curvature, said bifocal surface being embodied in finished form in said lens by temporarily laminating a plurality of lighttransmitting thin planar strips to form two lens blanks, forming said first spherical curvature on a face of one blank, forming said second spherical curvature on a corresponding face of the other blank, separating the formed laminations, selecting alternate lamination of each lens blank, and assembling and bonding said alternate laminations to form the bifocal lens.
 2. The lens of claim 1 wherein said second set of laminations has different light transmitting properties than said first set of laminations.
 3. The lens of claim 1, wherein said laminations have nonreflecting side surfaces. 